Spiral stairs of building have the functional feature for utilizing its space effectively as well as the design effect for attracting the beauty of building.
In view of the design of the spiral stairs, a handrail body thereof must be provided with a beautiful view. By forming a curve of the handrail more smoothly, the beauty of building is enhanced furthermore.
In view of the design, such handrails of conventional art have many disadvantages to be improved. The conventional handrails for the spiral stairs are made of pipe or steel rod which is to be bent in relation to the ascent of the spiral stairs as well as the spiral curve thereof. And it is a difficult technical task to form a smooth curve of the handrail which is an inconspicuous element.
Further, since the pipes or steel rods for the conventional handrails for the spiral stairs are bent at the site of building construction, its working is very burdensome, uneasy in assembling and welding, and subsequently expensive in cost. In the same manner, it becomes a very difficult technical subject to obtain a smooth curve of the handrails in flower beds, ships and other various fields.
In order to remove the aforegoing disadvantages of the conventional art, the present invention has been achieved.